The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 24, 2025
Filed:
Jul. 21, 2021
Jfe Steel Corporation, Tokyo, JP;
Shunsuke Sasaki, Tokyo, JP;
Ryosuke Tachi, Tokyo, JP;
Hiroyuki Yamasaki, Tokyo, JP;
Hiroyuki Fukuda, Tokyo, JP;
JFE STEEL CORPORATION, Tokyo, JP;
Abstract
A seamless steel pipe has a t/Dof 0.05 to 0.40, where t is a wall thickness (mm) of the seamless steel pipe, and Dis an outside diameter (mm) of the seamless steel pipe. The seamless steel pipe has a maximum depth d(mm)≤0.350 mm for defects in an inner surface of the steel pipe on a cross section perpendicular to a pipe axis. The seamless steel pipe has an average defect depth d(mm)≤0.200 mm for defects having a depth of 0.050 mm or more in the inner surface of the steel pipe. The seamless steel pipe, per millimeter of an inner circumferential length of the pipe, has at most 30 defects having a depth of 0.050 mm or more in the inner surface of the steel pipe.